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arXiv · 0902.0650

From Twists and Shifts to L-R asymmetric D-branes

Massimo Bianchi
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Abstract

In the first part of the talk, we discuss non-geometric twists and shifts and briefly review asymmetric orbifolds and free fermion constructions. These allow us to build Type IIB models with N = 1_L + 1_R and N = 1_L + 0_R models having few or no moduli. We then consider unoriented projections of the former and (`exotic') D-branes in the latter. In the second part, devoted to L-R asymmetric D-branes, we review how extended supergravity vacua in D=4 can be embedded in Type II superstrings. We then identify bound states of D-branes with residual susy and non-trivial R-R couplings. We discuss the N = 6 = 2_L + 4_R case in detail and sketch other extended susy cases. Finally we describe the resulting open string excitations. We conclude with some speculations and possible interesting developments.

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Massimo Bianchi. 2009-02-04. From Twists and Shifts to L-R asymmetric D-branes. https://doi.org/10.1002/prop.200900064

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